For Blair-haters, this is the perfect book. Wheatcroft's principal charge remains Blair's Iraq policy. He ignores domestic reforms. Whisper it not, but the past decade has seen a major redistribution via the tax system from the haves to the have-littles or have-nothings. A decade ago, my South Yorkshire constituency posted job adverts offering wages of £1.20 an hour. Workers had no statutory paid holidays. Pensioners had to choose between heating and eating. Social housing and schools had seen no refurbishment in two decades. Gay people could not enter into legal partnerships. There were no Muslims in parliament.

But for Blair-haters, none of this counts against Iraq. In 1995, the foreign secretary, Malcolm Rifkind, made a statement in the Commons washing his hands of any involvement in combating the crimes in Srebrenica. I sat in the Commons that afternoon, unable to believe my ears. My country was prepared to walk on the other side of the street as 8,000 Europeans two hours' flying time away were taken out and shot in cold blood.

Reading Wheatcroft's book, I now understand better the mentality of the Rifkinds, and of the 1930s foreign-policy realists who opposed intervention in Spain because it would make matters worse. Wheatcroft generously writes that "Blair is no totalitarian" and "Blair is no fascist", but we are also told that Labour is run by a "politburo", and he protests about "the Blair junta methods". Writing of Robin Cook's divorce, Wheatcroft declares: "Alastair Campbell broke up Cook's marriage by ordering him to choose immediately between his wife and his mistress." I worked as a parliamentary private secretary in the Cook Foreign Office, and Wheatcroft is wrong. Cook was at Heathrow in August 1997 en route to Colorado for a riding holiday with his wife, Margaret. His bodyguard handed him a mobile phone saying Campbell was on the line. An aide who was squeezed between Robin and Margaret Cook in the airport car recalls: "Robin took the brief message from Campbell informing him that the News of the World had the story of his long relationship with Gaynor, who later became his wife. Cook visibly shrunk into his seat as he took the news. All Campbell did was tell him what was going to be in the paper. The man who broke up Robin Cook's marriage was Robin Cook."

But such truth has no place in Wheatcroft's hyberbole. He makes the usual charges about WMDs but does not mention that the man who first described Saddam Hussein's WMDs as a real threat to Britain was Robin Cook. I sat behind him in the House of Commons as he used all his speaking powers to chill MPs with detailed descriptions of Saddam's arsenal. It was used to justify the military bombardment on Iraq which Cook initiated. Cook then had no qualms about using force against Saddam, just as he had no problem with bombing Belgrade and killing Serbs without any legal authority from the United Nations. Wheatcroft skims over the Balkan conflicts, but those who argue that Iraq was wrong in the absence of UN authorisation have to explain why Kosovo was right without UN authorisation.

There is another tiny difficulty Wheatcroft has to skate over. Iraq was the first major British military intervention authorised by the House of Commons. Of course, for the Blair-haters, when the Commons takes a decision they don't like, it proves all MPs are poodles and the Commons a supine instrument of the Blair junta. Yet Blair defended his Iraq policy endlessly in the Commons. Uniquely among leaders of G8 nations, he has agreed to do regular news conferences to which foreign journalists are invited, as well as to appear regularly in front of senior MPs of all parties who chair select committees. No previous prime minister has exposed himself to the media and to MPs to this extent. But, of course, there is nothing that Blair and his politburo can do that will please the Wheatcrofts of the world.

His discussion on Iraq contains nothing new. Sadly, for a man who knows France, he does not discuss the failure of the European powers opposed to Bush to do anything in 2002 to offer an alternative policy. France agreed the UN resolution of November 2002, which was a staging-post to the conflict. As late as January 2003 I was told by someone at the highest level of the French government that President Chirac would not allow Saddam to get away with any further defiance of UN resolutions. Saddam brushed away Arab League appeals to stand down, confident that his divide-and-rule tactics would ensure that the world's democracies would not be able to both fashion and enforce a joint policy. France's threat of a veto was greeted with amazed joy in Moscow and Beijing, as it collapsed UN pressure into US unilateralism.

Patrick Cockburn, the surest chronicler of the occupation of Iraq, records that the weeks after Saddam's ousting were a time of joy, of liberation. That it has turned to chaos is a global disaster. Germany's Joschka Fischer, the finest foreign minister of recent times, says that "jihadi fundamentalism is the new totalitarianism". He is right, and Wheatcroft has nothing to say about how we should handle this new endarkenment which wants to destroy everything that the democracies in Europe and North America have fashioned over centuries. He writes that the chancellor of Germany in this period was called Helmut Schröder, so perhaps it is for the best that Wheatcroft sticks to British sources to compile his indictment of Blair. And, of course, Iraqis do not exist in this book. Hundreds of thousands were murdered by Saddam and, equally tragically, many are dying today. All the fault of Blair? If only history and the world were so simple.

· Denis MacShane is Labour MP for Rotherham, and worked at the Foreign Office as a parliamentary private secretary and minister between 1997 and 2005.